#include<stdio.h>
int main()
{
	double a,b,c;
	scanf("%lf %lf %lfd",&a,&b,&c);
	float everage=(a+b+c)/3.0;
	if(everage>=60)
	{
		printf("NO");
	}
	else
	{
		printf("YES");
	}
	return 0;
} 
